Combined type-writing and computing machine.



H. M. BECKER.

COMBINED TYPE WRITING AND COMPUTING MACHINE.

APPLICATION FILED MAY 15. I9l2.

Patented Oct. 16, 1917.

B SHEETS-SHEET l R. M. BECKER.

COMBINED TYPE WRITING AND COMPUTING MACHINE.

APPLICATION FILED MAYI5. I9I2.

1,243,669. Patent-ed Oct. 16, 1917.

8 SHEETSSHEET 2- R. M. BECKER.

COMBINED TYPE WRIHNG AND COMPUTING MACHINE.

APPLICATION FILED MAY l5. 19x2.

1,243,669. Patented Oct. 16,1917.

8 SHEETS-SHEET 3.

8 SHEETS-SHEET 4- Patented Oct. 16, 1917.

R. M. BECKER.

COMBINED TYPE WRITING AND COMPUTING MACHINE.

APPLICATION FILED MAY l5. I912.

Illa-J ll's:

2w 2%. 5 NR 7 R M BECK ER. COMBINED TYPE WRITING AND COMPUTING MACHINE.

APPLICATION FILED MAY l5. I912.

Patented Oct. I6, I917.

8 SHEETS-SHEET 5.

R. M. BECKER.

COMBINED TYPE WRITING AND COMPUIING MACHINE.

APPLICATION FILED MAY 15. 1912.

1,243,669. 7 Patented 00a 16. 1917.

B SHEETS-SHEET 6- R. M. BECKER.

COMBlNED TYPE WRITHQG AND COMPUTING MACHINE.

APPLICATION FILED MAY 15. 1912.

Patented Oct. 16, 1917.

R. M. BECKER.

COMBINED TYPE wmnm; AND COMPUTING MACHINE.

APPUCATION HLED MAY 15. 912.

1,243,669. Patented Oct. .16, um.

8 SHEETS-SHEET 8- FIG. 20

UNITED sTAT sPATENT OFFICE.

RICHARD M. BECKER, OF NEW YORK, N. Y., ASSIGNOR, BY MESNE ASSIGNMENTSTO UNDERWOOD COMPUTING MACHINE COMPANY, OF NEW YORK, N. Y., A CORPORA- TION OF NEW YORK.

Specification of Letters Patent.

Patented Oct. 16, 1917.

Application filed m 15, 1912. serial No. 697,393.

To all whom it may concern:

Be it known that I, RICHARD M. BECKER, a citizen of the United States, residing in Brooklyn borough, in the county of Kings and State of New York, have invented certain new and useful Improvements in Combined Type-Writing and Computing Machines, of which the following is a specification.

This invention relates to a combined typewriting and computing machine of the Un derwood-Hanson type and more especially to a machine capable of both adding and subtracting, such as that described in application No. 626,550, filed May 11, 1911.

It is the object of this invention to enable, in this type of a machine, a change in the character of the computation, as from adding to subtracting, to be controlled from the typewriter carriage by the position thereof, so that the typewriting in a certain column or zone may'correspond to adding or subtracting of the computing mechanism according to the previous setting of the machine.

In the Underwood-Hanson machine used to illustrate the exemplification of this invention, pins corresponding to the numeral keys and to the particular denominational column, are set up so as to subsequently control in accordance with the numeral keys previously struck the extent of rotation of a series of computing wheels, so that the proper numbers are exhibited thereby.

In the subtraction operation, the computing wheels are rotated in the same direction as in adding. The pin-setting mechanism. however, is changed in setting for sub traction, so that a pin corresponding to one less than the complement of the number of a key struck is set up. The tens-borrowing operation is carried out and the computation rectified by giving all the idle wheels :1 complete rotation. unless one has been borrowed therefrom, through a setting up of the 9 pins, and a giving of an extra tenth of a rotation to the'unitscomputing wheel.

In application No. 626,550 above men tioned the setting for subtraction was obtained by the manual operation of a subtraction key. In this case arrangement is also made whereby a special tappet or stop. carried by the carriage, automatically controls the setting forsubtraction, The .tappet sets connections so that a subsequent operation of the general operator will trip the same to enable them to return to their normal position, "andat the same time bring into play a special subtraction setting mechanism. This latter subtraction mechanism includes a spring normally under tension, which acts at this time to pull on a rack so as to rotate a gear meshing therewith. The gear has a one way clutch connection with a shaft which operates to enable the power of the spring to rotate the shaft. On the shaft there is provided a cam which operates to set the subtraction controlling mechanism to its effective condition, en abling the subtraction action of the com puting mechanism. Incidentally, the bichrome attachment of the computing mechanism is shifted so as to print red instead of black. The spring is retensioned by a sub sequent operation of the general operator, which also acts to automatically change back from subtracting to adding.

Other features and advantages will hereinafter appear.-

In the accompanying drawings,

Figure 1 is a vertical section taken from front to rear with parts broken away to show the underlying structure.

Fig. 2 is a fragmentary horizontal sectional view. 7

Fig. 3 is a fragmentary perspective view showing a portion of the pin-setting mechae nism for both adding and subtracting, and also showing details of the automatic subtraction setting mechanism and its connection to the bichrome ribbon shift.

Fig. 4 is a fragmentary perspective view showing details of the subtraction setting mechanism afterthe same has been set by the anticipating tappet or stop, and in the act of being operated .by the cross-bar on the general operator.

Fig. 5 is a rear view in elevation partly broken away to show the underlying structure.

Fig. 6 is a fragmentary view showing a subtraction tappet orstop in the act of per forming its function to set the subtraction mechanism.

7 is a view of the parts shown in Fig. 6 showing the subtraction tappet passing ineffectively by the apposite mechanism during the return motion of the carriage.

Fig. 8 is a view of the parts shown in Figs. 6 and 7 with the exception that the tappet or stop is reversed in its position so that it will not reach the subtraction setting mechanism. and therefore will pass ineflectively over the same.

Fig. 9 is a fragmentary top plan view of the parts shown in Figs. 6 to 8.

Fig. 10 is a detached perspective view of one of the subtraction tapp'ets or stops.

Fig. 11 is a detail view showing the linkage for returning the 9 pins to their unset position on such of the column bars as may be raised at any particular instant when a numeral key is operated; the same being in its unoperated condition.

Fig. 12 is a view of the parts shown in Fig. 11 showing the parallel links of the linkage spread apart to return the 9 pin on the raised column bar.

Fig. 13 is a fragmentary view in elevation taken at right angles to the views of Figs. 11 and 12, showing one ofthe pins being set, and also showing the 9 pin on the same bar as raised and unset by the linkage shown in Figs. 11 and 12.

Fig. 14 is a fragmentary top plan view of the linkages for setting the pins either for adding or subtracting, and showing these linkages with the parts in a relative relation such that a setting of the pins for adding may be accomplished. 1

Fig. 15 is a fragmentary front view showing the indicator connected to the bichrome ribbon shift whereby the character of computation as to adding or subtracting being carried on by the computing mechanism will be indicated at this point.

Fig. 16 is a detail view partly in section from front to rear showing the subtraction setting mechanism which is controlled automatically by the subtraction tappets or. stops carried by the carriage. In this view the parts are all shown in their normal position.

Fig. 17 is a view similar to Fig. 16 showin the parts moved to a set position by a subtraction tappet or stop but with the slide of the trip prevented from upward movement by the cross-bar of the general operator.

Fig. 18 is a view similar to Figs. 16 and 17, except that the general operator is moved forward and returned so that the slide of the trip has moved upwardly to a position projecting in the path of the crossbar of the general operator. This view also shows the general operator 1n the act of rockmg the tri so as to lift the lock and .enable the tension spring to rotate the cam shaft, and thus set the subtraction controlling mechanism to its active condition.

Fig. 19 is a view of certain of the parts shown in Figs. 16 to 18, and showing the rack being moved by thetensionedspring so that the cam shaft has rotated to set the subtraction controlling mechanism, the shaft andcam having rotated but a portion of a cycle, that is; one-quarter of a revolution, and having still another quarter to move before stopping.

Fig. 20 is-a detail \u'e'w in elevation partly in section showing the means for giving an extra; tenth of a rotation to the un'its'comp ti gw l- Fig. 21 is' a fragmentary vertical section showing the subtraction setting mechanism at the instant of setting by the subtraction key, and before the subtraction key isreturned to its normal position.

In the Underwood Hanson combined typewriting and adding machine, illustrated in the drawings, alphabet keys 1 and numeral keys 2 (Fig.- 1) operate to depress levers 3, to vibrate bell cranks 4 to swing type bars 5 upwardly and rearwardly against a platen 6. The platen shifts to permit different types to print, being mounted in a vertically shiftable platen-frame 7 having a roll 8 to run on-a shift-rail 9. The platen frame is connected by arms 10 to a nonshifting letter-feeding carriage 11; said arms mounted on a rock shaft 12, which is journaled in said carriage, permitting the platenframe 7 to shift up and down. Said carriage 11 has a rack 12", meshing with a pinion 13 forming. part of a lettei"-feedi ng mechanism. The carriage is driven by a spring barrel 14. Each type-bar hasa heel 16 to operate a universal bar 17, which controls dogs 18 to coiiperate with an escapement wheel 19 connected to said pinion 13, so, that as every type key is operated, the carriage 11 is fed a.letter -space.

On rock shaft 12 are rigidly mounted two rearwardly extending arms supporting a rod on which is rotatably mounted a denomination sele'cting tappet 20, adjustable along said rod, and capable of being locked in any desired position by means of a tooth 22 engaging one of a series of notches 23 formed in a rack bar 24, also carried by said arms.

This tappet 20 has a tooth 25 to engage consecutively with jacks 26 and lift the lat ter; the tooth 25 being beveled or camshaped for this purpose, and the jacks being correspondingly shaped. The jacks are levers ,pivoted upon a rod 27 fixed on the framework; and, when actuated by tooth 25, each jack depresses one of a series of thrust rods 28. These jacks and thrust-rods are employed for the purpose of selecting the computing wheels to be operated, or of determining the denomination of the number which is to be added, or in other words, of determining the place in a column in which computing is to be effected The jack to be operated by the tappet :20, as the carriage runs inietter-feeding direction, is the jack of highest denomination, for instance millions.

The connection from the jacks to the computing wheels is as follows: The rods 28 at their lower ends are pivoted at 29 to levers 30, the latter pivoted loosely between'their ends upon afixed .rod 31, and extendin forwardly therefrom beneath a set of lin s 32, overlying which are forwardly extending denominational or column selecting 2 rack bars 33 for operating the computing wheels 34 at the front of the machine. Said'links 32 have pendent stems35 to be engaged and lifted. by the forward'ends of the levers 30, andalso rising stems 36 (Fig. 21) to engage and lift the wheel-operating rack bars 33. Each of said links 32 forms. a member of a linkage; the other members of which eom prise diagonal links 37 and a connecting link 38; whereby each link 32 is caused to rise about vertically. ,These linkages serve to form cross-connections between the jacks 26 and the rack bars 33: the denominational order of the latteiabeing the reverse ofthat of the former; the jack26 of highest denomination being at the right of the series, while the computingwheel 34 of highest denomination is at the left'of the series.

Each of' the rack bars 33 carries at its forward end teeth 39 to mesh with a pinion 40 (Fig. 1) with which each of the computing wheels 34 is provided.

Theeifect that eaoh jack 26has on its associatedrack bar-33 is .to lift the rear end of the latter, while theother rack bars remain in normal positions;\and the purpose of lifting or selecting the rack bar is to permit the setting of any selected one of av'ertically extending row of pins 41 thereon; the pins being set by means of said numeral keys 2.

Said numeral keys are, connected .respeetively to transverse pin-setting bars 42 overlying the pins 41, but incapable of reach ing the latter when-the rackibars 33 are down in normal positions; butif any rack bar is lifted by its jacki'26, in the manner already explained, then the depression of any numeral key- 2 (theearriage 11 remaining stationary) will-cause the corresponding setting-bar 42 to descend and engage the underlying pin 41, to force the 'latter to project down' below the lower'edge of its rack bar 33. This downwardly-projecting pin. then servesas a lug, by .which the rack bar =isdriren forwardly to rotate its'assd ciated computing wheel in a manner that will presently: :be explained. I

When-the carriage lleis moved to such a position' that the tappet -2O is'in the field of the jacks'2fi. and one ofthe latter is lifted by the tappet, if a-key 2 be depressed, it will pusli downa stem*43 to operate a linkage, whereof said'pin-setting bar 42 constitutes a'member: There are nine pins 41 (marked F. 1'- ".130 9, Fig.-21)'on'eaeh: rack bar. 33, forming a'rowextending longitudinally of said rack bar; and thelpins on all therackbars taken together form rows extending crosswise of the machine,,a bar 42 overlying each row. Each bar .42, (see corresponding linkages, Figs. 11 and 2) forms a link between opposite bell-cranks 44; being connected to horizontal arms of said bell cranks; the vertical'arms 44f offsaid bell-cranks are connected by horizontal links 45 these links 45 having wrists .46, engaged by slotted arms 47 fixed upon forwardly-extending rock shafts 48, carrying horizontal rockarms 49 just beneath and in position to be engaged by the descending key stems 43, Fig. 1. 'The manner in which each of the pin-setting. bars 42 overlies a transverse row of settable pins 41 is clearly illustrated at Fig. 3. The linkages 42, 44 and 45 are marked 1 to .9 (Fig. 2) and form a nest extending horizontally across the machine overlying the pins 41- and. their rack bars 33. I The. fore; most .of these linkages is ;operated. by the numeral key 1, the next rear linkage .is operated by the-numeral key 2, and thenext by the numeralkey 3, and so on; there being nine of the linkages. The forward pin-setting bar 42 being, as just explained, operated bythe numeral key 1, is capable of depressing the foremost pin 41 on anyof said rack bars33, This pin is situated so far forwardonsaid rack-bar, that only a minimum stroke isgiven to the latter by a subsequent operationof themachine; and hence the associated computing. wheel 34 is turned a minimum distance, that; is, one-tenthof a revolution. v The device that carries the rack bars forward is a horizontal bar'50, which is caused to move horizontally .fo rwardand pickup the raclabars 33 by means of the projected pins 41, so that the strokes of the. several rack bars, and hence of their associated computing wheels, depend upon whichpin in each rack bar was depressed, or in other words which numeral key was operated. The tappet 20 on the carriage selects the wheel, and any numeral key 2. -may determine-thee'xtent of rotation of the selected wheel. Upon the return of key 2, the. carriage lIHfeeds. and the tappet 20 lifts the next lower jack 26.

-Said horizontal-bar 50 forms a part of a general operator, which also-comprises a pair of slides 5l, 51, at opposite sides of the machine, mounted in suitable guidesupon the base and rigidly connected by said bar 50, as well as by a forward cross-bar 52 just beneath'therack bars 33; the slides and the bar taken together forming aframe, and constitutingthegeneraloperator of the computing wheels.- These slides are formed with racks '53, toa'nesh with-pinions 54 pivoted upon the: sidewalls of the machine frame, saidpinions-inturn meshing with segments 55:fixedwupon the opposite ends of a liorir zontal rock shaft 56 extending across the loo fill

machine and'carrying at one end outside of the frame a long-handle 57, which is swung forwardly from the Fig. 1 position to advance the general operator and cause the bar 50 to advance the rack bar 33, to turn the pinions 4:0 and computing wheels 34. Upon the return stroke of the handle 57, said crossbar 52 of the general operator engages shoulders 58 (Fig. 1) formed upon the under sides of the rack bars 33 and returns them to normal rear positions.

During thelast part of the return stroke of the general operator, a universal pin-restorei' in the form of a. horizontal plate or tablet 59 (Fig. 1) is caused to lift and restore all of the depressed pins 41 to their normal positions on the rack bars 33 (this being a function of said general operator). Said universal restoring plate is actuated by a cam 60, mounted upon the left hand slide 51 of the general operator to engage a rock arm 61 pendent from a horizontal rockshaft 62, the latter extending across the machine and mounted in the side walls of the machine frame, and having near its middle an arm 63 to engage and lift a projection 64- provided on said universal pin-restoring plate 59. The latter is mounted for up and down parallel movement by means of forward and rear ears 65, which are pivoted to horizontal arms of hell cranks 66, 67, the former loosely mounted on said shaft 62 and the latter loosely mounted on a shaft 68 parallel with said shaft 62. Said bell cranks comprise pendent arms 69 which are connected by a link or links 70. At the last part of the return of the general operator, the cam 60 engages the arm 61 and turns the shaft 62, causing arm 63 thereon to rise and lift said pin-restoring plate. It will be noticed that the cam 60 is pivotally mounted on said slide 51, to permit it to pass freely under the arm 61 during the forward stroke of the general operator.

When the rack bars are being returned rearwardly by bar 52 of the general operator, the pinions 40 turn idly, the latter h: ving pawl and ratchet devices, not shown.

The computing wheels are held steady by spring detents 72, Fig. 1, which engage gears 73 fixed on the respective computing wheels; said gears 73 serving also as tenscarrying gears. The tens-carrying operation is initiated by special teeth 74 (Fig. 20), one of which is fixed upon each of the computing wheels 34, in position to engage and operate, once in each revolution of wheels '34, an adjacent tens-carrying pinion 75 (F 1), the latter provided with a threetoothed gear 76 in position to mesh with and turn the gear 73 fixed on the computing wheel 34 of next higher denomination. Although the tens-carrying operation depends upon the actuation of a pinion 75 by the tooth 74 upon the computing Wheel 34, still masses such tooth merely initiate the tens-carrying operation, the latter being completed by means of one of a series of power-driven rocking segments 77. There is one segment 77 for each of the computing wheels except the units wheel; and these segments are fixed upon a transverse horizontal shaft 78 which has at one end a pinion 79 (Fig. 1), the latter meshing with an idle' pinion 80, which in turn meshes with the teeth 53 on the left-hand slide 51 of the general operator, so that the pinion 79 is rotated fo-rwardly and backwardly about a complete revolution at each cycle of movements of said general operator. The tens-carrying segments, however, are intended to rotate only in one direction; and hence the shaft 78 on which they are fixed is connected by a ball or other clutch (not shown) with said pinion 79, so that the rotation of the pinion during the advance of the operator is an idle one; the segment shaft 78 being turned only during the return stroke of the operator. In other words, during the forward stroke of the general operator, the teeth 74 on certain of the computing wheels 34 operate to set the tens-carrying pinions 75, and during the back stroke of the operator, the segments 77 engage the pinions 75 and complete the tens-carrying operations by giving one-tenth of a revolution each to the correspondin computing wheels 34. The tooth 74 on eac wheel 34 imparts to the tens-carrying pinion 75 one-ninth of a revolution; there being nine teeth on said pinion; and each segment 77 is intended to turn its pinion two-ninths of a revolution; each pinion being thus turned one-third of a revolution in all, in order to rotate the gear 7 3 and the next wheel 34 one-tenth of a revolution.

Every third tooth-on each tens-carrying pinion 75 is cut away, a portion 82 being left, however, sufiicient to be engaged by a spring detent 83; the tooth being cut away so that the tens carrying segments 77 may swing idly past the tens-carrying pinions when the latter are idle; the gap between the teeth adjacent to the cut-away tooth being suflicient'to permit the free movement of segm'ent'77. Thetooth 74 on any computing wheel 34, by moving the tens-carrying pinion 75 one-ninth of a revolution, turns said pinion into position for engagement by its associated segment 77 upon'the next return movement of the general operator; whereby said pinion is advanced an additional one-sixth, and the wheel 34 of next higher denomination is turned onetenth of a revolution. The segments 77 are arranged in spiral order onthe shaft 78, so that tens-carrying may proceed from low to high denominations throughout the gang of computing wheels during a single return stroke of the general operator, whereby all the wheels may be turned-from 9 to 0 progressively during said operator stroke.

--The machine is capable of subtracting as well as adding. Tn e ecting subtraction, the computing wheels are turned in the same direction as when adding. In subtraction, as inaddition, the movements of the computing'wheels are eifected'or controlled by the general operator above described.

" To' setfor subtraction by hand, a subtraction key :or finger-piece-UO is pressed. One of the functions of-this keyris to set all the 9 ins 4:1 on the rack bars 33. The handle 5 'of the general operator may be then=pulled forward, whereby all of the rack bars 33 are advanced and caused to turn their wheels each through ninetenths of a revolution] :-Upon the return stroke of the general operator; the. described tens-carrying mechanismzwilloperate to complete the revolution of each computing wheel through 360 degrees, except that .-of lowest'denomination the latter being advanced automatica-lly one notch by means "that will presently be explained. Thus ifsaid key llO be operated and'then' the handle 57 be swung forwardly and backwardly, 'all of the number wheels 34'Will be turned idly an entire revo-' lu'tion, even though'no ,numeral key is operated, and regardless of the initial posis tions-of the several wheels, so that the same readin' will be given .at .the sight opening lllas'efore.

1 If,-after'pressingfthesubtraction key, any one ofthe numeral keys is operated, as for instance the 'key marked 2, the 9 pin on whichever rack. bar 33 is in action,-=will be automatically restored to its normal idle position, and another of the pins 41. on said rack bar will be projected (by meanspresently toi be described), namely the 1 pin which 'is the second one forward from the 9 pin just restored. Hence,' when the handle 57 is operated, thetross-bar 50 will advance the rack bar in question only seven points, while the remaining rack bars are advanced nine points; and upon the return stroke of said handle, each number wheel will of course be advanced another step or unit movement. Therefore all of said number wheels will show the same reading as before, with the exception that one of them will show a number which is two less than the number that it previously showed. In efiect, two has been subtracted from the amount previously shown on the selected number wheel.

From the foregoing, it will be understood that at' the subtraction operation the numeral key marked 1 if depressed, must set a in 11 which is next forward from the 9 pin on the selected rack bar 33; the key marked 2 must depress the pin which is second forward from the 9 pin on the ee 1 lected rack bar; the key marked-3 must depress the third pin forward from the 9 pin; that -marked 4: must depress the fourth'pin forward; that marked 5 must depress the fifth pin forward; that marked "6;the sixth .pin forward; that marked 7 the seventh pinforward; that marked-8 the eighthpin forward; but the key which is marked 9 must not depress any pin, since nine from nine leaves nothing, and hence the selected number wheel must re mainstationary during the forward stroke of the handle 57, i. 6., it must drop nine points behind such wheels as are to make an entirei'evolution. In each case it will understood that: the 9 pin which has been previously set by the operation of the subtraction key 110, must be restored to its normal-idle position, so that the rack bar 33 whose pin is projected by the 1 key, will begadvanced one less than nine, or will drop behind 'to'the extent of one point; that whose pin was projected by the 2 key will be advanced :two less than nine, (dropping backtwopoints); that whosepin was projected by the 3 key will be advanced three lessthan 9, andso on; the rack bar coeperating with the. 9 key not being advanced at all. From this it will be understood that at .the forward strokeof the handle 57 the rack bars having pins set by means-of the numeral-keys will be advanced correspond ingly, 'and theirassoeiated number wheels will be turned accordingly; while all the remaining rack bars 33 will be advancedfull strokes,.and their wheels turned nine points. Certain wheels may also be turned each an additional point during the return stroke of thehandle 57 and the general operator connected theretoi The means whereby the subtraction key 110 shifts the connections between the numeral keys and the settable pins/9C1, so that the'desired result can be obtained, will presently be described.

, Assumingthat all the wheels read 0 at the sight opening 111, and that the subtraction key 110 be pressed back, and that the numeral Zkey bearing the figure 1 is depressed, and the handle 57 swung forwardly and then backwardly; the carriage 11 standing in such a position that the tappet 20 is connected through a jack 26 with the units rack bar 33, it will be understood that all'of the 9 pins on the rack bars 33 will have been depressed by key 110, and that the 9 pin on the units rack bar 33 will have been restored again to normal idle position by the key 1, and also that the pin next forward thereof will have been simultaneously depressed. The forward stroke of the handle 57 will have caused the cross bar 50 to advance all of the rack bars nine points, except the units rack, which is advanced only eight points, so that the numbernow appearing at the sight opening is 999,999.98. Upon the return stroke of the handle the.units wheel is advanced auto. matically an additional point, as Will presently be explained, While the remaining wheels remain ,inotionless, so-that the number finally shown at the sight opening is 999,999.99, Since the units wheel has not been advanced an. entire revolution from its 0 position, it has failed to operate the tens-carrying mechanism, and hence the Wheels of higher denominations stand inthe positions to which they were brought-at. the forward stroke of the handle 57, by reason of their 9 pins 41- having been alli set. by the subtraction key 110. It will thus. be seen. that the-effect of moving said key 110 is to cause 1 to be subtracted from every number wheel during theensuing forward stroke of the handle 57, regardless of where the number wheels may originally stand; and whether this loss of l is restored upon the return stroke of the operating handle 5?, depends upon the positions of the tens- Carrying members at the timea-JVhere a rack bar 33 has been unaffectedby any-of the numeral keys, it turns its .wheelf nine points on the advancestroke of .the.;handle 57, and. the tens-carryingrmechanismead. vances the;-same Wheel one;-point-.irpon the returnof said handle 57, unless :the'. operation of-certain of the numeral keys ;-has affected the ipins on one; or more of-zthe other rack bars 33in such amanner asz-to affect the tens-carrying mechanism so that it will fail to act in thisparticular instance on thereturn stroke of-the handle 57.

Assuming that the number shown atthe sight opening 111 is 000,088.88 i, and that it is desired to subtract a number which contains several zeros, as .forinstance 20.06, the carriage 11 is first moved to the thousands place, the subtraction-key is pressedback, and the numeral key 2 is operated. Then tlie numeral key 5 0 is strucktwice, and then the numeral key 6=.;. -=Thenthe handle 57 is drawn forward, turning each of the first four Wheels nine points. Atthe same time the thousands wheel is advanced two less than nine points (or seven=points), the-hundreds wheel is advanced nine points, the tens wheel is advanced thesame, and the-units Wheel is'advanced six less than nine points (or three points).. .In' 'other words, the thousands wheel and the units Wheel drop behind the remaining 'wheels, and the number appearing at the sight opening is 999,957,71. In advancing the thousands wheel seven points from .8 to 5 the associated tens-carrying pinion was turned by tooth 74:. The tooth 74: on'the units wheel also turned its-'tens-carrying pinion. It will also be understoodthat in turning nine points from 8 to 7 each of the tens and hundreds. wheels also advanced or set its associated pinion 7 5. Upon the return stroke on the handle, the'units wheelis advanced automatically one point,

will presently be explained, the units segment 77 turns its pinion 75 and advances the tens wheel to 8. The next segment likewise advances its hundreds wheel to 8 The next advances the thousands wheel to 6 and tens are likewise'carried on all the higher wheels, so that the number at the sight opening reads 000,068.82 Thus it Will be seen that at the forward stroke of the handle 57 some of the tens-carrying pinions 75 may be advanced by the special teeth 74,- while others may not; and at the return stroke ofsa'id handle 57, all of such tens-carrying pinions 75 as have been. so advanced. will be turned still more by their segments .77, in each instance advancing the wheelv of next higher denomination.

The subtraction operation thus involves revolving idly through an entire revolution such wheels as are not in use, and it involves the use of the tenscarrying mechanism in such a way that tens are in effect borrowed from wheels of higher denomination to such an extent as may be requisite, theltens-being borrowed during the advance stroke of the-handle 57, and being restored by the tens-carrying mechanism on the return stroke of the general operator only in suchrases. as are requisite.

=.As before stated, the subtraction key 110 shiftscertain connections whereby the numeral keys 2 set the pins 41, so that the key- 1 will set the pin next forward of the nine pin on any selected rack bar 33, the key 2 will set the pin two points forward of the'nine pin, and so on, to cause the se lected' number wheels to drop behind, each to 'a corresponding extent, at the general rotation of the computing wheels during the cycle 'ofsubtracting operations. The same nest of cross-links 45 is used in the subtracting operation, as in the adding operation heretofore explained; and each cross-link is associated with the same cross-row of-pins 41 as in performing addition; but at. the subtractingoperation the first key 1 instead of operating-the foremost cross-link 45, as in the adding operation, is connected to that link which is just forward of the rearmost cross-link. This connection is effected by means of a slotted arm 112, Figs.- 14, 21, which engages a subtraction wrist 113 provided upon the link in question; the addition wrist 46 on the opposite end of-the same link being disengaged and out'of-use at the subtraction operation. The shifting of the -arm 112 into engagement with"the wrist 113 is effected by the pressing back, of

the key 1-10,' whi'ch it will be seen, is attached to the frontend of a horizontal push rod llt, Figs. 1 and 21, pivotally supported at its rear end upon a rock-arm 115, and having between its ends a wrist 116, Fig. 21, which engages the lower end of a lever 11'? and presses it baolnthe upper end of said lever swinging forwardly to press in the same direction a uni'versalshifter bar 118, which extends across the machine and ispiv oted at its opposite ends in fixed ears 119'; the lower edge of said shifter bar engaging peripheral grooves or slots 120 in all of the forwardly extending rock-shafts 48which carry at their forward ends the key-operated arms 49. 'The forked arm 112, which is normally out of engagement with the subtraction-wrist 113, is heneeshifted forward into engagement therewith; but at the same time the arm "-17 which is fixed upon the same rock-shaft 18, is shifted out of engagement with the addition wrist 46 on the foremost cross-link 4:5. -.A similar operation takes place with re-' spect to each of the other crosslinks; arm 121, (Figs. 14 and 21) onthe second rock shaft 48 (operated by the key 2) slipping into engagement with the subtraction-wrist 122 on'the third cross link from therear, while the forward arm 47 on the same rock shaft slips out of engagement with the addition-wrist 46 on the second cross-link from the front. On the third rock shaft (operated by the key 3) arm 123 slips forward into engagement with the subtractiomwrist 124 on the fourth cross-link from the rear, while the other arm 17 on said shaft slips out of engagement with the wrist lflon the third cross-link from the front. Numeral key 4:

. controls a shaft 48 on which is fixed a rock arm 125, which at the forwardshiftingof said shaft slips into, engagement with a'su'btraction-wrist 126 on the fifth cross-link from the rear; while the forward armj47 .on the same rock shaft slips out of engagement with the wrist 16 on the fourth cross-link from the front. Upon the next rockshaft 18, which is operated by the numeral key 5, is but'a single rock arm 1-7, and this is shifted out of engagement with the additionwrist 46 on the fifth cross-link from the front, and into engagement with asubtraction-wrist 127 on the sixth cross-link from the rear. The key 6 operates a rock shaftwhich likewise has a subtraction arm 128, which is slipped into engagement with wrist 129 on the seventh cross-link from therear, while the rock arm e7 on this shaft is slipped out of engagement with the addition-wrist 46 on the sixth cross-link from the front. The rock shaftsoperated by keys' 7 and 8 are correspondingly equipped and shifted, the rock-shaft for thekey 8 having an arm 130 which is shifted into engagement with a wrist 131 on the ninth cross-link from the rear; this being the last link of the nest. The key 9' rocks the extreme right-hand shaft 18 of the series; and at the operation of the subtraction key 110, the arm 4.-7 on said shaft is shifted out of engagement with the wrist 16 on the rearmost cross-link 45 of the nest but'no' other arm is provided on thisshaft, since at the subtraction operation the shaft' turns idly, the. number wheel 34 which isat the timejassociate'd' with'said rock shaft'not'being'advanced by its rackat the forward stroke. of the 'eneral operating handle '57, and said :nunilier wheel hence dropping nine points behind the normal advancmg movement of the number wheels at suchstrokeiof said'handle.

The levers 49 on the forward. ends of said rock shafts farethick' enough to compensate for their forward shifting movements, so that thekey stems 4;3.may always engage the samejf'and it will be understood in subtracting tha't when"key"1 is depressed, the first cross-link 45; forward of the 9 cross-link, (which is thereariiri'o'st the nest) is thrust to"theleft, 'and the corres ending pin 41 is depressedilpon 'sueh rack-Ear 33 as happens to be elevatedffthj'atf when key 2 is depre ed; t sed i i b in 45 f m h re'armost jlisTopefated,'anda pin 41 is de pressed which is second from" the rearmost pin'on ainyjelevated rack 1321133; and/so on throughoutthe seriesj' no' p'in ll being depressed,however,iwhen the'9 key is opera'ted',"'for reasonsjus't given. Each of the keys 1 to 8therefore"sets a pin whose value is one less than'the complement of the key. The diagonal saw of subtraction arms intersects'the' rbw 'o'f addition arms. The 5 arm maybe regarded as a double arm, one arm or portion' to engage the 5 link and the other to engage the 4 link,

-Wh ent he subtraction key is pressed back to'swing thenri'iversal shifter bar 118 forward, to shift fendyvi'se' alljofthefrock shafts 48, a latch 132 is snapped by a spring 132: to a position behind said universal shifter bar, tedetain' the same in its effective position, so that the user of the machine may release the I subtraeti'on key 110, and have both'hands free to manipulate the type-operating keys.

. Ithas been above stated that operation of the'subtraction key 110 sets 9 pins 41'0n all of the wheel operating rack bars 33. To do this, an" the fracks are simultaneously lifted; said ar n 115, to-.which the-rod or stem 11511 is pivoted,being fixed upon a rock shaft 133,'"whieh has a. universal bar or bail 134: extending acrossunder the rear ends of all of the rack bars 33, so that when said v stem is thrust rearwardly, the shaft is rocked and all of said rack bars are lifted; j The "9 pins on said racks ar'eall'simultaneously depressedforprojected below the rack bars by a universal bail lalffixedon thesame rockshaft'l34l which carries the lever 117 (Figs; 1 and ;.said bail engaging and'dep'ressing the forwardends of levers 139 (which are connected to the 9, pins) sufficiently to force'the9 pinsto; project below the rack bars, Where they may be all subsequently engaged, by, the, crpss, bar. 50 of, the general operaton so that at the forward movementof, the latter, all vof their number wheels may b e,rotated nine points.

As above explained, Whenever all the pins have been set by the subtraction key 11Q,and numeral key has been thereafter p t e ze-p pon. ny se afite \vheel-operating rack bar 33, the originally set 9 pin on the samejraok bari's'glan t'q maticall restored to normal idle position. Thisis e y mea s i a universal lis e operable by all of the numeral keys, 'It comprises a transverse 'endwise-movin' 135, Figs. 1, 11, 12 and 21, balrcr i ks 136, 137-, and a transverse downwardlymoving link or bar' l38 in position tgdepress (Fig; 21) any of a v set. of levers 138; whichar'e mounted upon the rack bars 33 and connect; ed to the 9 pins to move thelsa'm'e lever is pivoted between itsends at 1 10 (Fig; 1 t its a kb r 3, a do t it orward end fits in a groove l tlix lijniedfinthenwl, pin 115' and when any rack bar by'the carria etappet 20 (through a iack 26, etc an any numeral key" '2- iS. depressed, the universal link l38, will down the lever 139, as shown inflEigr 13 thus st n h p m a elevated rack to 'itsnormal condition. All of h k y pr e meksh tsfih e pr e n r e n'seds h up ta n ar s 1412', to engage corresponding 1:43 on said cross] link 135, to' .efi'ect the restoration toiiormal-idlecondition of the 9 pin previouslyset by the si btraction key 110; a spring 144 '(Fig. 12)' serving to return this universal pin-restoring linkage to' normal position. upon the release of the depressed numeral ke'y. Normally the arms 142 stand back of the wrists 1A3 and are hence inefiectivea heraddin 'operation; but when theshafts 48 are shi ted forwardly by the subtraction key 110, said armsareshifited therewith into positions for engaging the wrist s143, The subtraction key 110 returns tonormal position as soon" s released, together with the rock shaft 133, and the ball 13%, the weight of the bailand of the rear end of the racksbeing sufficient to return the parts. As before explained, the operation of the subtraction key 110 is intended: to set the machine to give a complete revolution to all: of the computing -v'vheels which have rack bars 33; and in order to efi'ect this, the tens ca rryingr mechanism is depended upon, the wheels being given an advance rotation of nine points at the forward strpke of the generaloperator' handlefi'f, and, if required, n additional advance of one point by th tens-ca mechanism at the return stroke of h g ne al QQQIQ Y- The ns-carrying m ani m f vers n t ra e, he l i awhae ibat there srrovid d a p cia evi e to, efi etthe nec i ies d an e of he units wheel a single point at the return strqke, of the v general operator, preferably at the initial portion of said return stroke, before the operation of the, tens-carrying mechanism. A slide bar 158, Fig. 20, somewhat resembling the wheel-operatin rack bars 33, is mounted at theright of-t e nest t withe s, 3 a'ndy provided with. Sing e. Setta P1 .1 pr f r b in in wi hin pi so aid r k bar T e subtraction key l-lodiits this special bar 158, swe l. a h a -.1 33, and e d P 1 ncounters a fixedabutment 160 during the up' w ard moyement of bari158, and is forced to emie rm t e b wls of aid a Whereit is engaged by the cross bar 50 oi he g ne al 0 exams a the l s re ie the forward strofiefoi, the latter, whereby the ba 158 is thrust forward, men age and operate an, armflfiLoi abell-cran to the ot rarm 1 2 sf w eh is p vo e a p w max g'ucer i l fifi b a prin' 1 was age .el' sn' e h we 3 zed to the un ts wheel;3 1. "llheefiect of the forward moyement off the bar l5 8ris to swing down the the bellcrank, pullin down thepawl 163 to positionito engagert 'e succe'eding tooth of the wheel 73. A spring 54%. retx a i e. b l -c a k ,,Pa nd be; 11 19 no po i ion l siw v rei wln h z qths W e 73 and he whee to theextent of oneetenth'of a revolution, soithlat the next higher number thereon shown at the Sight opening 111. The univa ap w mmg;pl 9, an ear lfibltorestoreithepin 159 on the bar 158, hat 'esre the. u i swhe p wl 16 In, he i s z ioqdi -yp m ng m c e, the types: strike through a ribbon, which is shown at Eig 3 as comprising. an up er stripe 179 one color and a lower stripe 171 of another color, said ribbon being threaded through a vibrator 172 which is connected toa frame 173, the latterfixed by 175mm universal bar 17, which re ciplfqcates ateyerytype stroke. As shown inPatent No 926,( )50 to F. A. Cook, the vibrator 172 isconnected to a lever 175, the latter qomprisinglan arm 176 provided with us e Mower-0929 i t s tofengaige slotted ears 179, 180in an'actnathead 180, which is adjustably connected to I a bracket 181 fixed upon. said universal bar framel'lflnsaid actuating head having a, guide pin 182 to'slide in a slot, 183'in said bracket 181. The actuating head 180 is conneotedby a link 1852 ,(W hieh vibrates idlyat the type strokes) to an. arm 185 fixed upon forwardly extending rock shaft 186, having at, itsforwardend keys 187, 188, whereby adjustment of the actuating head 180 is e eeted, to bring it into engagementwith either, Wrist or to varythe throw of hem 1. .5 witspe t e .59 a s to'a pin 222.motmtedzon.a.s1ide223. The slidex223 is secured so: as to rock with azplate leverf224, but a-lso;so.as to have a vertical movement relative thereto, by means of plurality .of pin-andslot-connections 225 and 22.6. Theslide223. and the plate 224 may;together be termed a trip. Although the tension,ofthespring22l tends to raise the.=s1ide-.-223, ;this.action is prevented, as will: be 'seen bytreference 'to 'Fig. 17, by the top end of the slide abuttingr against {the cross-bar. 50. of .:the, general. operator so that so long asthe general operator is in its normal: inactive -position,-the-slide 223 of the trip will ybe-prevented ;.from moving upwardly. As-soon, 'h0\VB"BI',,:flS the, general operator is :moved forwardly during: the action of running-:up' ag'computation, the cross-bar wil1 .move from above :theslide 223-permitting.thewspring 221 to act'to raise the slide 223 i302 a'position projecting in the pathof-thebarfiO on its ireturn movement. The slide in its raised position :isshown in Fig-18.

When' the general-operator returns to ;its normal po'sitionythe bar 50 will engage the slideand rock the :trip as a wholewhich comprises theslide- 223 and therlever 22%, so that an arm:227*on;the lever will engage an arm: 228 on a lock 229 :so asto raise the latter against thetension of a spring 230. It-Will be: noted in passingithat this .rocking action arlso' releases rthe'latch- 21"8 inasmuch as the latter has. an.;a'rm=21=8-'Which extends in the pathpfamovementof .-the. trip. The lock 229 is supported for vertical movement by a ."pinand slot-connection 231 and has an overvhang' dog'232 'which "is normally located in the path of a pinu233 on a rack bar 234. :This' relation 'of the pin 233 to the lock '229'prevents the movement of the rack bar 234- to the rear. A spring 235 is normally undera tensiontending to pull1=the rack-.bark234 to the rear so that as soon as the-lock 229'is raisedf'this spring will act.

The rackiofithe rack bar 234 mesheswith awpinion-236z-so that as-soon asthe spring 235 acts, 'thegear 236 will be rotated. The gear 236 has aone way clutch connection with a cam shaft 237 Which-is'shownin the form of ahall-and socket clutch connection 238. ThlSWti'HtGh connectionis so arranged that when !the springiacts, the-gear 236 in rotatingxwilli lalsorotate" the camshaft 237. Anreturn-Totation ofwthe' shaft 237 during asubsequent return-.anouement of the rack bar 234iisz1pifevented;howevery'by a. spring detent .239 which engages a matchet 240 mcuredi-toithelshaft 237. .-.Also. secured tOitl'lG shaft 1.237 there is provided I 53; double roam 241 which when the shaft-237 rrotates, cams against. a :follower 242 :as indicated in Fig. 19;rwhereby: is link-243 which carries :the fol-- lower 242 '1SLmOV-8d .rearwardly, so. as-to-rock mes-pee theiarni- 11-5 to which it is pirotallyisecured as welhas ,thesuhtraotion -key bar 114. After-the cam 241 and the shaft 237. have rotated to the Fig. 19 position,qwhich is but half .wa-ycf their motion they .Will .continue on so that the long end of the cam24l' will escape from :the follower-242 allowing the-subtraction rod 1141 to return to its normal passive position. aThisewithdraws the bails-13 1 and 13s to a position cleanof'the rack bars and the. pins. .Therack bar 234; remains in its actuated .position :until a. subsequent: actua ti on. of: the general .operator. The link-243 may be guided-ally havinguits opposite end sbifurcated and z-having i' the forks thereof extending on opposite sides of the shaft=237. 'Itwill thus be seen that the computing mechanism may? .be: setf for: :subtraction by a :tappet or stop carriedby the carriage as Well -as by 'the subtraction key 110.

The spring-235' is .r-etensioned .When the subtraction computation .is run up by. the cross-bar -50 engaginga hook-244 ons.-the

rackbar234. In order that the latoh'132 there is provided in one of =the side bars of the general operator amotch 245 having: a cam side-.246,- which at ithe .forwardamoven1ent.of the generalloperator is adapted to engage a spherical enlargement 247 .on an arn1-= 248. This: arm is securedto a .rock shaft 249 which also has. secured thereto an arm. .250. v hen. the-arm'2 18 :is swung to rock the shaft-249 the arm250- comes into engagement with an arm 251mm the latch 132 and rocks the latch against the tension of-xits :spring so as-to permibtheuniversal shifter bar 118 itowreturn rmderthe-tension of its spring to itsmormaltadding position, whereby the pin setting -mechanism is shifted so th'atit :W'lll act to.'set;theupins for adding. 'The .rock; shaft :is returned for action by a spring .252 which :isisecured to a pin 253 on the vrock shaft-2.49. In addition to releasing the universal shifter-bar 118 by releasing the-:latch 132, the rock shaft-249 returns townormal the bichrome attachment. To do this the rock-shaft .249: is provided with an arm-254 connected bywa 'link'2551to an aun -2 56 on the rockishaft r192 sothat the biehrome shifting; .rneeh-anismwill areturned simultaneously with: the return: to

adding, 4 whereby =.the subsequent printing will @be black insteadof red.

' The=linkt255rhx15 a apinwaznd .slotl'osttionconnection; t-Wit'l'i the :arm 256 so that the ribbommechanism can be shifte'd'with out =in-terferi-ng with the computing mechanism.

Advahtageistaken of :the "shifting of the bichrome attachment of the typewriter nib- I ture'26l ivlien-;the ribbon mechanism 'is avranged to print 'red corresponding to asubtraction action of-th'e computin mechanism.

In the operation of the device considering more specifically thecontrol -of the stated the computing mechanism from the carriage, a subtraction tappet is 'set in the position indicated iii-Figs. 6, 7 and 105 with the projection 'thereof extending-"down wardly in such a'position that it will engage the follower 204i Itis to be'notedthat the subtraction tap'pet'mus't be setto correspond "with fthe'stop'ping of the carriage for the columnf preceding the column in which it is desiredt'o'subtract." For-example, we will assume'thatyin the column preceding the one in Whichit is desired to subtract," an adding action is to be carried on. To bring therarriage to a position'so that'the numerals can'be'printed'on. a Worksheet-inthe preceding adding column, one of the tabulatin'g keys 196 is struck so that the associated plunger 199 will come up into the path of this"subtractionta'ppet or stop 5202'.

The movement of the tappet or stop 202 over the fol1ower"204 will depress one end of the lever 205'so that the' thrust'link 212 will rock the 'shaft'214 therebyraising the pin 217 (see Figs. .4: and '16" to 18) until the pin i's-caught by the latch 218. This action will stretch-the spring 221- placing itunder :i tension'inasmuch'as-the'slide 223 engages the under side of thecross-bar '50 on the general operator so that it ispreyen'te'd from further upward movement. 'when the type- Writing keys have been actuated to set up the accumulating pin's'on the column bars, the general operator can; be'actuated'to run up the accumulated 'computationon the computing wheels; As the general operator moves ifo'rward'in 'Ic'a'r'ryin'g out this operation, the cross-bar 50 thereon will 'move from its position above the slide 223 so that the spring 22l is free'to thrust-the slide'223 upu ardly iinto' position shown in Fig. 18. As the eneral operator returns; the cross-bar 50 will come into'engagemen't with thesli'de 223 of'the mp, makin the trip so that the latch 218 will be engaged therebyv :to release the pin 217 Hand-thus permit therock shaft- 214 to turn back t'o-its normal position carrying the .111 ssociated parts back to their nor-r mal positions. 'The rocking-of'the trip-also causes the oifset arm 227 to engage the arm 228 *and' lift the 1ock229 so that the dog 232 thereof iwill no ilonge'r preventthe -movement-oi the rack bar 234. The spring 235 then acts'i to 'pullI'ther-ack bar rearwardly causing: the rotation of the pinion 236 which. transmits it's rotation to the-cam shaft: 237, The camshaft rotates-through one-half 0151a revolution causing one-end of the cam -to shift'lthe'zlink 243 rearwardly by engaging with 'theifo11owen-242' sothat the am 1 15 will be swun to rockthe' shaft 133. The bail 134'carr1ed--by= the rock shaft -133-wil1 be swung upwardly to raise all of-the column bars 33,'f-as well as the bar 158, whereby all-:of-rtheif) pins and-the pin-159 may be set. :The same action will draw rearwardly ens-the subtraction key rod llfl so that the wrist-lldthereon Will come into engagement with the lever 117' to'rock the shaft 13s to v swing the-universal bail-5134 do wn to'set the 9pins and th'e'pin 159. Theleyer 117 thrusts the universal-shifter bar 118 forwardly so as'to change thepin setting mechanism from theadding connection'tiothe subtracting. connection; 'Whereby, ,instead' of theipin' eorresponding to the number 5 struckbeing set upg 'the pin'corresponding to one less than the complement of the number struck willbe s'et up, using the exchange value:betweendenominations (i. 0;, ten in this instance) as the base in obtaining the complement. the same time the link 190 "will be drawn' on *to rock the shaft 192 a nd thus raise the link 193 to adjust thebichrome'attach nent so that instead of printin-g black it will print red. The-actuation of the blCll1'OI11e" 'Sl1lft will rotate the-shaft 18fiso that the indicator-260 willbe swung to bring the indicating letter S in opposition to the aperture 261 showing that the operationwhich will be carried on in the next column is-s'ubtracting one. -After the adding computation has been run up in this manner'and the computing mechanism set for subtractin'gfoneof the tabulating =keys 196 is struck to bring thecarriage to a position correspondingto the subtracting column. Numeral ikeysnare then actuated-to transcrihe the' numbe'rs'to theworksheetand at the same time the'p'in-setting mechanism will set up pins corresponding to one l'ess than the-*eomplement ofthe'; numbers struck. The 9: p'i s=on= such of the pin-bars as have p'iiis s'et' by" the striking of theynumeral keys will be unset by means of the universal link 138 through the combined action of the numeralkeys'""e;nd the raising of the pinbars. When the completenumber has been;

thus set up, the. general operator is caused to move -fonwardly by an,actuation of the handle 57 and the .number accumulated in the usual manner, on the computing wheels as despribediin a plicatien N 0. 626,550.

As the genera operator moves ,forward, the crossbar-.150 thereon comes inengage ment with thehook 24A and .retensio'ns the spring1235. As soon as the pin 23.3 has slipped under: the cam.- surface of the lock 229,"this:1ock is automatically drawn down by :the spring230 until the dog 2332 comes in back oi theipin=fl33 and prevents the movement of the rack-bar 234 under :the treetion of the spring 235. lhe return of the lock 229 to its normal position-will also-return the trip to its ,normal position. :iVhen the general operator returns, it moves away from the ,hook 244: leaving it out in-its extended position. .At the .initial forward movement of-ithe general .operator,-.the- .cam

surface 246 of -the notch..-2,45 therein thrusts the arm 248 upwardly,. s0 astorock the shaft 249. M lken the shaft 249 ,rocks, ;:it carries upwardly the -arm-250 until it swings the latch 132 out-of engagement with the-univ'ersal shifter liar 1-18 permitting this bar to return to its -1nor-mal position carrying v with it the. series-of-rock shafts with the connected arms. soithat the arms 47 thereon once i more engage :the wrist 46. corresponding. to

anadding-setting of thepins, or in other words, returning-the pin settingmechanism to :the state shown in Fignla. At the same time the rocking of the shaft 9A9 causes a swinging of the arm 254 30 thatthe link7255 pullsdownon the arm 256 to rock the-shaft 192. :Therocking of this shaft in .turnlpulls down on the link '19?) so that-the ribbon shifting mechanism is once more adjusted to bringthe blackportion ofthe ribbon into play in-place of the red portion. This action rotates the-shaft 186 so as to swing the indicator 260, bringing theletter A in opposliion torthe aperture'fifil indicating that the adding action has come in play. lt will thus be seen that the ,change to subtraction can be controlled from the carriage as well as from the subtraction key, and that when the subtraction action has been completed the mechanism will automatically return to its. adding 'state.

Variations may .he resorted to within the scope of the invention, and portions oi the improvements may .be ,used without others.

Having thus described my invention, 1

claim tation devices either to'determine addition or tozdetermine subtraction by said computing mechanism, and carriage-controlled means for-determining whether said keys shall, control said .pre-limii'iar representation devices-to determine ad ition-or subtraction.

2. he combination with typewriting mechanism, including a carriage. andnumeral keys, of computing mechanism, pins for controlling the extent oi movement ofsaid computing mechanism, means controlled-from said keys for setting said pins, and means to enable said carriage to determine whether addition or subtraction shall be-performedbythe said computing mecha-;

by said tappet on the movement of said can.

rlage for manipulating said means to controltheoharacter of. computation; said tappet beingadjnstably mounted on said carriage so as tqbe oapableot being rendered efi'eetive or. inefiective.

1.4; The. combination with a. typewriting mechanism including. a carriage, of a computing mechanism, means for controlling thecharacter of computation carried on by said computing.mechan-ism, means normally tending to actuate said first-mentioned meansto .change the characterof computzv tion, a-lock for,restraining saidsecond-mentioned means, a trip for said lock normally inoperative, andcarriage controlled means for renderingsaid trip operative, said C0111 puting mechanism having means to actuate said ,trip whenoperative, so as to cause the release of lock.

5.. The combination with a typewriting mechanismincluding a carriage, of. a computing mechanism, 1 means for controlling the character of computation carried on by said computing mechanism, a tappet carried by said carriage, and connections operated by said tappeton themovement ofsaid carrlage for manipulating said means to control the character ofcomputation; saidconnectionsduclu ding a two-part means, one of said lparts hsmg'yielding when approached from one direction to enable. anineffecti ve return movement of. saidtappet with said canriage.

6. 'lhe combination with isetting up mechanism, rot.computing mechanism, a, general operator for, runn ng nto. the computing m n s mews-s t pI i-w en n ue mechan sm; n me t enab e s i 

